Reversible primary battery



L. WR. PULLEN. REVERSIBLE PRIMARY BATTERY.

(No Model.)-

` Patented July 6, 1897.

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UNITED STATES PATENT EEIoE.

LEoN w. rULLEN, on CAMDEN, NEW JERSEY, AsSIGNoR or TIIIRTEEN-sIxTIErI-IS To CHARLES L. IILAUDER AND ALBERT E. BAINBRIDGE, orPHILADELPHIA, PENNSYLVANIA.

REVERSIBLE PRIMARY BATTERY.

SPECIFICATION forming part of Letters Patent NO. 585,699, dated July 6,1897. Application led October 23, 1896. Serial No. 609,807. (No model.)

To all' whom it may concern:

Beit known that I, LEON W. PU'LLEN, of the city and county of Camden,State of New Jersey, have invented an Improvement in Reversible PrimaryBatteries, of which the foll lowing is a specification.

Myinvention has reference to batteries; and it consists of certainimprovements which are fully set forth in the following specification 1oand are shown in the accompanying drawings,

which form a part thereof.

The object of my invention is to providea suitable construction ofbattery which shall be light in weight, efficient in operation, ca-

pable of being readily charged and discharged without injury,inexpensive in construction, and durable in operation.

My invention is especially designed for secondary batteries, but may beused with prizo mary batteries also. I'Ience I do not coniine myself toany special use.

Heretofore oxid of manganese has been used in primary batteries as adepolarizer without an attempt to increase the voltage of the bat- 2 5tery but in my invention the peroxid of manganese is employed as anViwrnpwgmtl` powder mixed with iinely-dividec carbon and a concentratedsolution of sulfuric acid for the purpose of producing a salt ofmanganese 3o as the basis of the cathode for increasing the voltage andwhen combined with the other elements, as set out in this application,capable of being charged like a secondary battery with a still furtherincrease in voltage.

In carrying out my invention I employ a negative electrode formed bymixing together powdered coke, graphite or plumbago, and an oxid ofmanganese (preferably the peroxid of manganese) made into a thick pastewith con- 4o centratedsulfuric acid. The oxid of manganese is theoxidizing element. This electrode is provided with one or moreterminals, preferably in the form of a piece of carbon extending downinto the mass of the electrode.

4.5 An electrode of this character is preferably arranged in a sealedcondition within the battery-case and is separated from the positiveelectrode by means of a porous diaphragm cell or cup containing sulfuricacid, prefer- 5o ably in a dilute condition. The positive may be formedof zinc and preferably arranged centrally Within the porous cell. Inoperation the powdered coke or amorphous carbon and graphite act as theconductor for the current from all portions of the negative electrede,the carbon tending to reduce the weight of the same while acting as aconductor and the graphite acting to keep down the internal re`sistance. In practice the amorphous carbon, which is preferablynelygpushed gas-retort 6o coke, such as would 'pass through a Kmq..mesh, is thoroughly mixed with the graphite or crystallized carbon, sothat all particles of the former are practically incased or inclosed ingraphite, and at the same time is also intimately mixed with powderedperoxid of manganese and the entire ingredients formed into a pastycondition by the addition of concentrated sulfuric acid. This changesthe oxid into the sulfate of manganese. It will be seen 7o from thisthat the particles of graphited amorphous carbon act as an excellentconductor of electric currentv and at the saine time maintain the entirenegative electrode in a porous condition, so Vthat the decompositionnecessary for the proper electrolytic action may take place throughoutits entire mass with the greatest facility. The best results aresetcured by having the plumbago ground as fine i as possible-such,forinstance, as is used for 80 polishing by lithographers. Themanganese; should be ground to about the same iineness as the plumbago,though inferior results can i be secured when it is not so finelysubdividedh l The electrode formed of this mixture is in- 8c closed tohold it against expansion and may be employed in a primary or secondarybattery as desired.

My invention will be better understood by reference to the accompanyingdrawings, in 9o 'Whichv Figure l is a sectional elevation of a secondarybattery embodying my invention, taken on linee@ m of Fig. 2; and Fig. 2is a sectional plan view of same, taken on line y y of Fig. l.

A is the outercase or box and may be formed of glass, rubber, metal, orother material, if" desired.

C is an inner porous diaphragm cup or chamroo ber, preferably ofasbestos, unglazed porcelain, or terra-cotta.

F is a centrally-disposed electrode of zinc arranged Within the porouscup.

B is the negative electrode and consists of the intimate pasty mixtureof amorphous carbon, graphite, sulfate of manganese, and concentratedsulfuric acid hereinbefore described. The preferred proportions of theseingredients, which I have found excellently adapted to the purpose inpractice, are one part of graphite by measure, a half part of crushedgas-retort coke, one-quarter part of peroxid of manganese, andsufficient concentrated sulfuric acid to produce a thick spongy mass.The sponge so formed is forced into the case between its Walls and theporous cell or diaphragm and preferably surrounds the latter. Theterminal D may be made of carbon, metal, or any conducting substance andis inserted into the electrode B and projects above. This electrode isthen sealed Vpermanently in position by a suitable sealing substance, assealing-,Wax E.. Any form of Wax not capable of ready melting by lov:lheat Will suffice. The porous cell isl filled with dilute sulfuric acidG and may be sealed by a cap J,Which prevents evaporation and at thesame time centralizes the positive electrode F. II is the positivel andI the negative conductor leading from the electrodes. Vhen mixing theingredients, certain reactions occur, producing greatheat and convertingthe concentrated sulfuric acid and peroxid of manganese into manganicsulfate. In the subsequent operation of this cell in discharging thesulfuric acid attacks the zinc, forming the sul* fate of zinc. Theconcentrated sulfuric acid in the negative electrode becomes diluted.These reactions produce a current between the electrodes and in theexternal circuit.

In charging the battery the reverse operation takes place, namely: Thedilute sulfuric acid is decomposed, settin g free oxygen,which combinesWith themanganese to form a higher oxid, and the sulfate of zinc isdecomposed with the deposition of metallic zinc on the'positiveelectrode. The hydrogen set'ffree in the negative electrode combineswith the oxygen fromy the decomposed sulfate of Zinc and forms Water,which dilutes the sulfuric acid `in the porous cup, Whi le the sulfuricacid in the positivey electrode is again bro u ght to the concentratedcondition. These reactions Will explain the nature of what mainly takesplace and may be assumed as the reactions of the battery,notwithstanding that some more com.-

plex reactions no doubt occur in con juncture` that the proportions ofthe several ingredients may be varied Without departing from the spiritof the invention.

The number, shape, or configuration of the battery-cell or its parts isimmaterial, as the shape and materials of the porous diaphragm or cellmay be varied to suit the ideas of the designer, the form shown vbein gthe simplest construction and excellently suited as an illustration ofthe general features of the invention.

What I claim as new, and desire to secure by Letters Patent, is-

l. A reversible primary battery comprising a suitable cathode, adepolarizing massin contact therewith and consisting of a mixture offinely-divided carbon, a salt of manganese and concentrated sulfuricacid uniformly distributed throughout said mixture and an anode arrangedin" adilute electrolyte.

2*. A reversible primary battery comprising l a suitable cathode, adepolarizing mass in contact therewith and consisting of a mixtureoffinely-divided plumbago, concentrated sulfuric acid and a saltof4manganese, andv an anode arranged in a dilute electrolyte. f

3. A reversible primary battery comprising` a suitable cathode, adepolarizing mass in co n tact therewith and consisting of a mixture offinely-divided amorphous carbon and plumbago, concentrated sulfuric acidand a salt of manganese, andan anode arranged in a dilute electrolyte.'

4. A battery consisting of an outer case, an inner porous diaphragm cupor vessel, a positive electrode arrangedy Within the porous cup ordiaphragm, dilute. sulfuric acid Within the porous cup and surroundingthe positive electrode, and a negative electrode consisting offinely-divided amorphouscarbon and graphite mixed with sulfate ofmanganese and concen trated sulfuric acid.

5. A battery consisting of an outer case, an inner porous diaphragm cupor vessel, a positive electrode arranged Within the porous cup ordiaphragm, dilute sulfuric acid Within the porous cup and surroundingthe positive electrode, a negative electrode consisting of finelydividedamorphous carbon and graphitey mixed with sul-fate of manganese andconcentrated sulfuric acid, a seal arranged above the negative electrodeand connecting the outer case with the porous cup, and a terminalextending from Without the cell into the mass of the negative electrode.

6. In a battery an electrolytecontaining case, a negative electrodecomposed of an intimate mixture of finely-.divided amorphous carbon,graphite and sulfate of manganese, a positive electrode consisting ofzinc, a porous diaphragm between the positive and negative electrodes,dilute sulfuric acid surrounding the positive electrode, andconcentrated sul-y furicacid intimately mixed with. the negativeelectrode,

7. An4 electrodefora battery consisting of anintimate mixture ofpowdered gas-retort IOO coke, graphite, sulfate of manganese, and aconcentrated electrolyte substantially in the proportion specified,namely, one part of graphite by measure to one-half part of coke andone-quarter part of oxid of manganese, in combination With a conductorextending from the interior of the electrode outwardly.

8. Au electrode for a battery consisting of an intimate mixture ofpowdered gas-retort coke, graphite, sulfate of manganese, concentratedsulfuric acid substantially 'in proportions speciiied, namely, one partof graphite .by measure to one-half part of coke and the quantity ofsulfate of manganese produced by mixing one-quarter part of oxid ofmanganese with concentrated sulfuric acid, in combination with aconductor extending from the LEON W. PULLEN.

Vtitnesses:

R. M. HUNTER, WM. D. EVANS.

